The present invention relates to the field of graphene and, more particularly, to the field of graphene devices.
Phase transitions are a dramatic example of macroscopic order arising from the microscopic interactions in a physical system. Small changes in the coupling strength of the microscopic interaction can produce distinctly different orderings. This coupling can depend on a variety of external factors such as temperature, magnetic field, or pressure. However, in any electronic phase transition, the coupling strength invariably depends on one essential factor, the density of electrons between interacting elements.
Need
Using the electric field-effect to tune the conductivity of semiconductors forms the physical basis of the consumer electronics industry. However, the ability to tune other electronic properties such as superconductivity and ferromagnetism (see, Ahn, C. H. et al., Rev. Mod. Phys. 78, 1185-1212 (2006) and Ahn, C. H., et al., Nature 424, 1015-1018 (2003).) has met with relatively limited success despite significant applications. The major obstacle to this end has been finding materials which not only have the requisite electronic properties but that can also be gated.